Abstract

This study was conducted to determine the effects of different diet on protein contents of cow milk. A total of one hundred and eighty (180) individual cows of three different breeds (jersey, HF and cross bred) were divided into three dietary treatments groups along with a control diet consisting of simple green fodder (GF). The dietry groups included cotton oil cake (COC), mustard oil cake (MOC) and maize seed cake (MSC). Results of protein contents of fodder (FOD) in comparison with concentrates that is, F-COC, F-MSC, F-MOC improved the protein contents significantly (P < 0.01) When fed only FOD, the protein contents was 32.85 μg/ml (3.3%), which increased to 34.08 μg/ml (3.4 %), 34.03 μg/ml (3.4 %) and 34.15 μg/ml (3.4 %) with the addition of F-COC, F-MSC, and F-MOC, respectively. Feed back response of the caseins and whey proteins was observed in sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) profile by resolving these proteins upon 15% SDS PAGE which showed remarkable variation in the banding pattern of all caseins i.e., α-caseins, β-caseins, κ-casein and whey proteins β-lactoglobulin, α-lactalbumin and showed prominent bands after the dietary treatment.

Key words:  Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), α-caseins, β-caseins, κ-casein, β-lactoglobulin, α-lactalbumin.